The last person to step foot on the moon was exactly 50 years ago this month, with Nasa's former Apollo 17 commander Eugene Cernan taking the famous steps.
That was just three years after Neil Armstrong made history by becoming the first person to step foot on the moon in 1969.
And back then, many expected people taking the steps would become more common as technology continued to advance.
But that hasn't been the case, with a now massive five-decade gap between now and the last person to walk on the moon.
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NASA has promised that we will soon see US astronauts back on the moon in the coming years, possibly as early as 2025.
But why has it taken this long?
Well, a former NASA administrator Jim Bridenstine, has said it is not because of technology or science limitations as many would have expected.
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The man who ran the agency during the Trump administration told reporters in 2018: "If it wasn't for the political risk, we would be on the moon right now.
"In fact, we would probably be on Mars.
"It was the political risks that prevented it from happening."
"The program took too long and it costs too much money."
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In the past, astronauts who visited the moon would collect rocks, take photos and perform experiments, amongst other duties.
But the Apollo program did not give them enough time to establish a lasting human presence on the moon.
However, that seems to be changing with NASA's Orion lunar spacecraft program, where it is hoped humans will be living on the moon for a prolonged period of time.
Speaking to BBC's Sunday with Laura Kuenssberg back in November following the launch of the Artemis rocket, NASA chief Howard Hu said humans could be living on the moon in the next decade.
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He said: "Certainly this decade, we are going to have people living for durations.
"Depending on how long we will be on the surface, they'll be living, they'll have habitats, they'll have rovers on the ground.
"That's what we are also working on at NASA, so not only are we able to work in delivering people to the moon, but getting people on the surface of the moon, they still have to have infrastructure.
"Ultimately, it is more than living, it is really about science and geological aspects of it."
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He continued: "It's the first step we're taking to long-term deep space exploration, for not just the United States but for the world.
"I mean, we are going back to the Moon, we're working towards a sustainable programme and this is the vehicle that will carry the people that will land us back on the Moon again."